docs: def namespace_inclusion_builder(namespace: Strings) -> NodePredicate:
      """Build a predicate for namespace inclusion."""
      if isinstance(namespace, str):
          def namespace_filter(_: BELGraph, node: BaseEntity) -> bool:
              """Pass only for a node that has the enclosed namespace."""
              return NAMESPACE in node and node[NAMESPACE] == namespace
  
      elif isinstance(namespace, Iterable):
          namespaces = set(namespace)
  
          def namespace_filter(_: BELGraph, node: BaseEntity) -> bool:
              """Pass only for a node that has a namespace in the enclosed set."""
              return NAMESPACE in node and node[NAMESPACE] in namespaces
  
      else:
          raise TypeError('Invalid type for argument: {}'.format(namespace))
  
      return namespace_filter